Computed Tomography Beam Hardening Correction Based on Non-linear Segmentation

Abstract

This paper aims to eliminate the hardening artifacts in computed tomography (CT) images caused by the polychromatic X-ray spectrum. To this end, a polynomial fitting correction method using non-liner segmentation method was developed through projection space optimization for single medium (water) and the mixed media (water-bone), and verified through simulation and phantom experiments. Unlike the traditional image space optimization strategies, the proposed method has low computing load and few noises, and only requires a one-off image reconstruction to remove the hardening artifacts. The experimental results show that the proposed method can remove CT hardening artifacts and improve the accuracy of image reconstruction, indicating that the project space-based correction method based on non-liner segmentation method can effectively eliminate artifacts and restore the true CT values.